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<DIV><FONT face=Arial size=2><SPAN class=765220502-02122006>We've been running
memcached in our production environment for several weeks now quite
successfully but have noticed that volume of internal traffic on our
servers is quite unevenly distributed, varying anywhere from 2-3Mbps up to
30Mbps. After looking into it a bit it was clear to us that this was a result
memcached gets. What we're finding is that since a key is only stored on one
server, keys with values that are large, or more often the
case values that are accessed frequently cause one server to be accessed
quite a bit more than others.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=765220502-02122006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=765220502-02122006>We can't put a key
in more than one spot (nor do we want to), but the more I've thought about it
the more I believe that there might be some value in a mechanism that self
adjusts key locations by moving heavily trafficked keys to less
heavily trafficked servers. </SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=765220502-02122006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=765220502-02122006>Say for example that
10 keys are accessed every page request and the hashing mechanism puts
all 10 keys on a single server (say out of a pool of 10 memcached
servers). Over time (based on access rates or some other suitable
metric) this mechanism would ensure that those 10 keys are evenly distributed
across all 10 memcached instances leveling off network
traffic.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=765220502-02122006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=765220502-02122006>It's a thought at
any rate - has anyone else dealt with this kind of
issue?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=765220502-02122006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=765220502-02122006>Cheers,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV align=left><FONT face="Arial Rounded MT Bold" color=#808080 size=1>Darryl
Kuhn<BR>Chief Technology Officer<BR>Skinit.com</FONT></DIV></BODY></HTML>